In the same price bracket, you will get about the same performance. Or, at least so close that it really does not matter.
The GTX650ti might be the strongest, with the 7770 next.
If you are targeting a specific game or two, look for some benchmark results for those games specifically. It can sometimes make a difference.
In general, most prefer the drivers from Nvidia, and the amd cards seem to be priced more agressively.
Don't anguish over minor details, you will get good value for your money from any of them.